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    Re: parallax of the sun
    From: Henry Halboth
    Date: 2004 Sep 21, 22:41 -0400

    Bowditch (1909 edition) contains a table of the Sun's parallax in
    altitude - ranging from 9" at 0-deg to 0" at 90-deg. As stated by others,
    the median parallax in altitude per this table is 6" at 50-deg. Should
    there be any interest, I will gladly publish this table, although actual
    calculation is rather simple.
    On Mon, 20 Sep 2004 20:07:34 -0400 Fred Hebard  writes:
    > I use the parallax of the sun in clearing lunar distance
    > observations,
    > and haven't done any for a while, until this evening (about 1.5-2.5
    > minutes out).  It's usually 0.1' of arc.  Is it tabulated or
    > mentioned
    > in the Nautical Almanac?  I couldn't find any mention of an actual
    > value.
    > Thanks,
    > Fred Hebard
    > P.S.  We're coming up on another equinox.  I, for one, wouldn't mind
    > another discussion of how it's determined.  I know it's old hat to
    > proficient astronomers such as Herbert Prinz, Geo Huxtable, Frank
    > Reed,
    > etc, but for the rest of us...!

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